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gomoX writes "As seen on C|Net , Linus has announced that the pre-2.6 series will be starting in early July. Despite not having been able to meet the release goal for 2.6 in June 2003, the next stable version is not as far away as you may think. You can take your guess based on the fact there was a 9 month period between first test version of 2.4 and the official release of 2.4.0 on January 2001."

In fact, 2.5 isn't that bad right now... certainly, it would be crazy to use it on a production system unless you really know what you're doing[1], but it's quite usable, and the scheduling has really improved.

[1] in which case you probably wouldn't use it on said production system...;)

I played around a bit with.71-.73, but the big thing that got me was that my mouse speed in gnome was sped up by about 10x over 2.4. I had to set the accel down to the lowest setting in gnome to make it usable, compared to about the 25-50% setting with 2.4. Of course, there is no similar setting for GDM.

I'm guessing this is due to the new keyboard/mouse modules, but who knows. Hopefully this is one of the things that will get shaken out when 2.5 and 2.6 become more mainstream and the KDE/GNOME folks se

I've been using the various revisions of the 2.5 series for a few months now. You would not believe how much more responsive X is. Well, you might, but that's not the point.;) It's been great, disk i/o is a bit faster, and the only problems I've had were with binary-only drivers.

Afterall Linux is open source, meaning anyone can hack the Linux kernal & create their own Linux 2.6.

So why doesn't that happen? & what gives Linus & co the authority to determine the next Linux revisions? I'm not saying he shouldn't, I just wondering why it happens this way when AFICS open source should means its a free for all.

There's no reason why you can't test it out on your current distro, except the usual caveat of "be careful, this may corrupt all your data", which applies to just about everything. But it's probably safer to use a fresh new partition.

That said, it's not the easiest thing to do, but it's also not the hardest. Building the kernel is very easy: download the latest source, extract it into/usr/src/ and...

make menuconfig

(Going through all the different options takes a while. Don't forget that almost all

Additionally there seems to have been some mucking around with tweaking the adaptive scheduler so X gets more time when it needs it. The performance metrics have been kind of squishy, but the general consensus is that X and related 'interactive' processes are more responsive.

As of 2.5.72 I think, the Matrox framebuffer at least compiles again. There is too much screen corruption on my 8mb G200 for it to be really usable yet...but its an improvement over the previous total breakage.

You can take your guess based on the fact there was a 9 month period between first test version of 2.4 and the official release of 2.4.0 on January 2001.

You might think that this was due to the birth of Linus' daughter Patricia. However, Linus actually spent those nine months cutting and pasting our code into the Linux kernel (there's so much of it, which is why it took him so long). Also, I am Patricia's real father.

You might think that this was due to the birth of Linus' daughter Patricia. However, Linus actually spent those nine months cutting and pasting our code into the Linux kernel (there's so much of it, which is why it took him so long). Also, I am Patricia's real father.

-- Darl McBride

won't you introduce us to your brother Darl, and your other brother Darl?

There was some hesitancy, upon the official release of kernel 2.4, based upon some bugs etc...

I'm wondering, does the kernel - generally speaking - get more and more stable. For example, will the first release of 2.6 be more stable than the first release of 2.4. I realise that there are new additions to the kernel, and with that new problems will probably emerge. However, comparatively speaking, does it make sense that the kernel's evolution will lean towards stability with each release in the cycle, or will it generally be unnoticable?

2.4 actually had some fairly serious flaws in the middle of it, but the modifications that were done that caused those flaws were, imho, necessary for further evolution.

Certainly pre-2.6 should squash out most bugs, however !! remember the vast majority of Linux users out there are NOT likely playing with 2.5.x or will be with pre-2.6!

The stress tests that come from 2.6.0 being announced and suddenly being unleashed upon tens of thousands more users (or hundreds of thousands more machines) than 2.5.x is will shake out all remaining serious flaws.

First of all, there are going to be a lot of kernels which start 2.6 before 2.6.0, due to the whole stabilization process. Secondly, I think that distros will have a more substantial role in testing the kernels than they have in the past, relative to individual users, so the big stress tests will come when IBM, Red Hat, and Oracle pick up 2.6-pre1 to test; in the past, the big stress tests came when 2.4.0 got a lot of end users to start testing. Third, Andrew Morton is intending to be a release engineer, which Linus has done badly in the past (that not being what his style is good for), which will mean that 2.6.0 will be carefully tested, unlike previous.0 versions.

Of course, this is due to evolution is the process of releasing stable series kernels, not evolution in the kernel code itself; through the middle of 2.5, everything got broken, and has now mostly been fixed.

In message <fa.n9kl75v.1nugol@ifi.uio.no> [google.com] ,
Linus himself admitted to releasing 2.4.0 because he "decided that enough is enough, and that things don't get better from having the same people test it over and over again." (In short, "we know it's still buggy as hell, but we hope more people will help solve that--if we just have them believe it's production-ready", right?)

I have absolutly nothing to add of a technical nature to this story, so I will delude you with a rambling trip down memory lane (comprised completly of anecdotes from 2.2).

My first taste of linux was phatLinux on my brand new p2-400 (128MB of pc 100 ram I liked). 3 months later I had built a sub 400 dollar computer to play around with and bought (yes paid money for) Linux Mandrake 6.5 from Wal-Mart. From there I began learning about this kernel thing (and my joys when I found make menuconfig and make xconfig, have you ever tried make config? ewww...) Well that went fine and fun, I added options, made modules all the fun stuff you do, but it was still in the same 2.2 vein that came with mandrake. Then 2.4.0 final was relased and I compiled and installed my first new kernel. Everything was new and faster. DevFS was a godsend, the ppp and bsd compression routines made my modem fast (or somthing I went from 2.5 kb/s downloads to 5-6 kb/s after recompiling). Since then I have also come to love dri, premptive and low latency patches, and all these other backported goodies. I am waiting on 2.6 final before I play with any of the new features (I didn't play with 2.3 or 2.5). Ok I am done. And I didn't even mention Gentoo... oh wait... damn.;)

Back in my day, all we -had- was make config. And that was a new thing then! I may be recalling incorrectly, but I think the first ver of Linux that I used actually used a config.h with defines.. I may be wrong, though, that might be other software.

Tell us more grandpa! Tell us about the time you wrestled and maintained 8 AIX servers single-handedly from your homebuilt Linux box! Or about the time Linus got lost and asked you for directions and you went on a whirlwind big-city adventure!

actually, I logged into an AIX box once.. probably in the very early 90's.. it didn't have ANY GNU tools installed, so I was lost as to why nothing worked the way I expected it to, and went back to BSD machines primarily...

At the time, I don't know if GCC and company even -worked- on HP/UX or AIX (I know they do now, although the last time I used HP/UX, it was still fairly well crippled compared to most other *nixes in the libc area) at the time.. but i was pretty thoroughly disgusted that I couldn't get -any- of the software that i wanted to run on these machines to run, because they were written for gcc.. which I thought was the normal for the world at the time. doh.

It'll be nice when it finally comes out, because I'll be able to point people doing audio work to Linux. Right now I have to say "well, Linux is better than Windows for this, but only if you apply the low-latency, pre-emptible kernel, and variable HZ (with HZ set to 1000) patches," which is a bit more involved than most people who are just doing audio work want to deal with. Once 2.6.x comes out I can just point them to the stock kernel.

2.4 latency also stinks on my laptop regardless of what I'm doing. Once every few days my machine just sits there with the disk grinding for 5-10 seconds (yes I upgraded to the latest kernel for RHL 7.3, same problem, used to happen once a day). It would have been nice if you could just echo something into proc to tell it it's not a server.

Is that the 'locate' database updating itself? On Debian I think that happens by default every 24 hours, at some time in the middle of the night. Basically builds a list of all the files on your hard drive, so you can do "locate blah" and quickly find where files are without searching the hard drive each time.

Another possibility might be to check if DMA is on; sometimes the kernel won't turn it on, depending on your config and hardware. Try "hdparm -d/dev/hda" (or whatever your hard drive is). If it s

Try Redhat 9, you just have to add CDCEther to the/etc/hotplug/blacklist file

Interesting. I'm using RedHat 9 and CDCEther for my cable modem. It works fine except from the need to reboot my cable modem once a day. So what is it with this Zaurus, and what driver does it use instead?

There's a lot of complaining about code-freezes for the kernel not being code-freezes. People gripe about major changes being introduced in the last days of the development version.

I think the problem is the standard explanation of 'even kernels are production, odd kernels are development.' Whether he says so or not, it's clear that branching to an even version does not mean that it's a production kernel...branching to an even version begins the code freeze. Up until they call it 2.6, there's going to be large changes to the codebase. Once Linus calls it 2.6, everyone knows they can't put in major changes, but basic bug-fixes only. Therefore, it's never until a few months (or a year) after the even series starts that it's really a production kernel.

Software development managers would hate this...lots of kernel developers hate this...but love him or leave him, that's how Linus works.

Nah thats not true, there is a freeze at the end of development kernels.

However you no matter the less right.Why? Because only a few people use uneven series. So they are tested not really well. You can ask people millions of times to test the final 2.5.x releases, they will stay with 2.4.x.

However as soon 2.6.0 is released all will jump of it, and test in broad enviroenment, so it takes some even releases until most issues are done.

It's our social behaviour that defines this reality. Not a way the linux

Linus has made it clear time and time again that most people simply will not use development kernels, and he releases versions to get people to use them and test them accordingly. Linus lives in what we will call "reality", while everyone else lives in some nice little far away place where the towels are oh so fluffy and the air smells like warm rootbeer.

That's what I like about Linus. He cuts through the BS and actually does things based on reality, not on some twisted view of how things should be.

That's why there's going to be a substantial 2.6-pre series, and why Andrew Morton is going to be the one to release 2.6.0. The goal is for 2.6.0 to be a production release, which means that 2.6.0 can't be the first 2.6 kernel. Fortunately, kernel versioning supports the creation of 2.6 kernels which are before 2.6.0, and Linus understands that his skills are not in release management.

The real step needed for stability is testing by a wide variety of people. This should actually be easier to get than in the past, since a much larger portion of the front-line testing these days is done by the various distributions, who are not getting into the "enterprise software" business, where they have to do substantial research on whether the software works on different systems before releasing it. And distributions are generally a lot closer to the development process than random individual users are, so they can be more easily convinced to start testing a stable series in advance of the.0 release. Furthermore, there's a lot more testing and verification infrastructure these days than in the past, from the Stanford checker (which catches a lot of unsafe usages in obscure drivers without having the hardware necessary to actually run them) to various test labs.

There's actually quite a bit more effort put into making sure that end users get a stable kernel these days than in the past, as more business software companies promote Linux more heavily. IBM will make sure that they know at all times the status of 2.6 kernels with respect to any bugs that can be triggered on any of the hardware IBM ships, and they'll make sure that Linus and Andrew know whether a kernel is suitable for 2.6.0, at least from IBM's perspective.

The real question is whether Linus will manage to hold off starting the 2.7 series until 2.6.0 is released. (Personally, I doubt it; I bet Linus will want to release 2.6.0 before Andrew is willing to, and I bet Linus will decide that the current version may not be good enough for production, but it is good enough to start further development, and Andrew will agree that people who want to work on 2.7 aren't going to do anything more useful for the remaining 2.6 problems at that point)

I hadn't noticed that, but wow, it's an excellent thing if true -- I think Andrew Morton is one of those rare people who not only has an immense clue, but is careful and thorough enough to release something that really will be stable. Maybe he's even better than Alan Cox in that respect...

Personally I'm looking forward to the 2.6 release because I'm the proud father of a new architecture in the 2.5 series -- the v850! Of course now I'm continually fr

I think it is safe to say nobody knows if Reiser4 will go into the stock 2.6 kernel, but I think the principals would like it to happen, and depending on how well the Reiser4 beta performs this summer, it should be possible, as long as it does not appear that adding the Reiser4 code would disrupt existing code.

I think it's probably refferring to the User mode Linux patch perhaps? Which allows one kernel to act as a parent for another to allow a sandbox to run a kernel in. Helps with debugging and telling someone you're giving them a dedicated server when you have six kernel instances running on the same box.

What about that? Will we be finaly able to switch kernels without a reboot?

I did that back in the 2.2 days with monte [scyld.com]. Later with 2.4 kernels I did a few changes, added a feature I was missing, fixed a bug and such stuff. In case you want to see it [daimi.au.dk]. But it was never completely stable and lacked SMP support.

kexec might be a better alternative. AFAIK it is being maintained and might even have made it into the 2.5 kernel.

"What about that? Will we be finaly able to switch kernels without a reboot?"

I did that back in the 2.2 days with monte. Later with 2.4 kernels I did a few changes, added a feature I was missing, fixed a bug and such stuff. In case you want to see it. But it was never completely stable and lacked SMP support.

kexec might be a better alternative. AFAIK it is being maintained and might even have made it into the 2.5 kernel.

It was only a couple of years ago that knowledgeable people were calling this idea ridiculous, and giving good reasons, however progress has marched on, and we're actually coming within sight of it. The basic challenges are much the same as for hotplug cpus, hotplug memory, process migration in a cluster, and yes, kexec, all of which are being worked on or already working. So I'll go out on a limb and predict that hot-kernel swapping will be demonstrated during the 2.7 timeframe. It won't be perfect, but such things never are in the first cut.

The thing that makes hot kernel swapping practical is the stable api between userland and the kernel. Big changes there are few and far between, and they can be special-cased.

What happened to devfsd and lvm? I know they were talking about replacing lvm, and I was wondering if the new code is in place?Also, I read somewhere that the developers were unhappy about devfsd, since 'nobody was using it'. I'm using it, so I'm hoping they don't remove it.

I don't know if devfs is gone yet, but it's gonna be replaced by sysfs sooner or later. Lvm on the other hand is gone, replaced by device mapper, on which both lvm2 and evms2 are built. Evms2 looks extremely well for a nice gui volume management.

I've been hearing though other channels that the IDE layer rewrite improves the IDE subsystem to the point where SCSI emulation won't be needed to drive an IDE CD burner. Can anyone confirm or deny this? If so, this will probably become my main reason to switch to 2.6 (although there are quite a few secondary ones too). Thanks linux team (and IDE rewrite folks)!

You are correct in assuming you don't need ide-scsi to emulate a SCSI host for burning cdroms in 2.6, but it has nothing at all to do with the IDE rewrite.

2.6 has support for queueing "generic scsi" commands through the block layer, using the same mechanism and transport as the regular read/write file system requests. So we can overload the sg (scsi generic) SG_IO and provide the same functionality for non-scsi attached devices (such as atapi burners). With a recent cdrecord, you can give the device with -dev=/dev/hdc for instance.

Additionally, cd burning is now zero copy. The user space data buffer is mapped directly into the kernel for the dma operations. DMA is supported on a 4-byte boundary, where 2.4 and previous has required sector alignment (512 bytes) for any atapi dma operations.

I would tend to say you'd need to modify your apps so that they'll run correctly with the new ALSA interface for sound support - although it supports OSS/lite emulation pretty much perfectly (as far as I know of)

Also, modules names have (I think) changed, so a change in the init scripts would probably be useful. It depends on your distro though - I'd say distros like Slackware and Debian will have guides or automated tools for migration. Commercial distributions will probably have to release a new version (RedHat 10 ? Gods).

Although maybe I'm wrong, I never managed to get a working 2.5.x kernel on my Debian box =)

Also, the old OSS modules are still in the kernel. I haven't tried them in 2.5, and they are marked with a big DEPRECATED, but they're still there.

Note, of course, as I've said elsewhere, you do need the new module-init-tools [kernel.org]; I'd imagine that would be the most likey reason you'd have trouble getting a 2.5 kernel working, followed closely by an out of date/broken driver.

I just read the
FAQ [kernel.org] (Mostly for developers). One part caught my attention:

Q: How does the module remove code work?A: It stops the machine by scheduling threads for every other CPU, then they all disable interrupts. At this stage we know that noone is in try_module_get(), so we can reliably read the counter. If zero, or the rmmod user specified --wait, we set the live flag to false. After this, the reference count should not increase, and each module_put() will wake us up, so we can check the

I just read the FAQ (Mostly for developers). One part caught my attention:

Q: How does the module remove code work?
A: It stops the machine by scheduling threads for every other CPU,
then they all disable interrupts. At this stage we know that noone
is in try_module_get(), so we can reliably read the counter. If
zero, or the rmmod user specified --wait, we set the live flag to
false. After this, the reference count should not increase, and
each module_put() will wake us up, so w

The Windows kernel hasn't changed significantly since the NT4 -> Win2K change. The biggest improvement in the XP kernel was pre-faulting the pages of large processes. Meanwhile, in 2.6, the block I/O layer, VM layer, scheduler, and sound system are brand new. And the whole kernel was made preemptible! Shortly after 2.6, ReiserFS 4 (which looks very promising from initial benchmarks) will be released. In all, 2.4 -> 2.6 will be like NT4 -> XP!

PS> Before anyone bitches about rewrites being a bad thing, look at things this way. Such extensive changes are necessary for the continually growing range of systems Linux is expected to run on. 2.0 and 2.2 were greatfor single CPU servers, or SMP machines with only a few processors. 2.4 is very usable for heavy-duty machines with many more processors. 2.6 (along with the changes that help interactivity) will make an excellent kernel for desktop machines and workstations. In 2.8, the focus will be on optimizing the core algorithms to run on large-scale NUMA machines.

Why would anybody moderate that a troll? Bad spelling does not qualify as a troll. There is actually a great deal of sense in that posting. Somebody have to try out new kernels and have them crashing before the bugs are found. Even great kernel hackers makes bugs, but bugs are found and fixed. So please say thanks to the great hackers and the brave testers.

I'm posting this anonymously because I'd be ashamed to have my name tied to defending Windows. Your comment is definitely true for versions of Windows up through ME. But I've been running XP on a Sony Vaio for the past fourteen months, and I have never had to reboot. In fact, I don't even know if XP has a blue screen of death, cuz if it does I've sure never seen it.

Contrary to longstanding contention here on Slashdot, one's personal experience with an operating system on a single computer (especially o

I can tell you emperically that I've seen more "Internal Server Error", "Server too busy to handle your request", etc. messages from IIS than from Apache. donotcall.gov, as a matter of fact, has been having reliability issues right from the outset.

Ahahahahahaha! Netcraft.Com has it in black and white. IIS on Windows 2K Server.

Windows XP is stable, but the process scheduler just isn't very good. I use NetBeans and Mozilla a lot, and the machine just dies every so often (for a while). Pressing CTRL-ALT-DEL doesn't do anything until windows realizes that it needs to stop jacking off or whaterver it's doing in the background. It'd be nice if I could kill processes quickly like I can in Linux.

All in all, I'll be happy to have my Linux box back from the repair shop. I'm just using my old iMac/233 now. With Linux it's more usuabl